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Are Arrays in java stored in contiguous memory?

Are arrays in Java truly stored in contiguous memory like in C++?

Java’s official documentation does not explicitly state that arrays are contiguous in memory.

Unlike C++, where the standard guarantees contiguous memory for arrays, Java leaves this up to the JVM implementation.

My observations:

1. Arrays are objects in Java, and all objects are stored on the heap.

2. Heap memory in Java is dynamically allocated and managed by the Garbage Collector (GC).

3. Heap memory is not guaranteed to be contiguous, especially as memory usage grows and fragments.

4. Different JVMs may implement array storage differently, especially for optimization, alignment, or memory compaction.

Unlike C++, Java does not guarantee that arrays are stored contiguously.

It depends on the JVM implementation and the current state of the heap.

So while array access in Java behaves as if the array were contiguous (because of fast indexed access), under the hood — you can't rely on it like you can in C++.

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Added on Jun 4 2025
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